Best way to splice aluminum wire underground

av8rMay 1, 2012

We have approximately a 400 foot underground run from the house to a gate near the street that powers the opener and a few receptacles. The receptacles stopped working and after uncovering a plastic junction box that was buried just a few inches deep out near the gate we discovered some corrosion and water inside the box. The original installer ran several what looks to be about #6 aluminum wires and inside the box that was buried spliced the aluminum wire to solid copper conductors that then go to the 3 receptacles within about 20 feet of this box. I want to re-splice these connections and run new copper conductors from this box to the receptacles. Everything is in conduit. What's the best method for the splice since it will be underground and it looks like it may be exposed to water? I don't think there is enough slack to get the junction above ground unless I dig back and cut the conduit and move the junction back a few feet. Should I drill a hole in the jbox to allow the 1/2 inch or so of water to drain? Thanks in advance.

Check out your local electrical supply house, and ask them for a Polaris block. They come in all different sizes and types, but you should be able to figure out what you need if they have them in stock. If you search Polaris block you will see what it is. These little jewels have made my life so much easier.

Polaris or NSI blue tap connector. It is suitable for direct burial/wet j-boxes. They are also suitable for either copper or aluminum and each conductor terminates separately so there is no problem with dissimilar metals touching. Sure, drill a hole. Water will always find its way in. It doesn't hurt to give it an easy way out.

U missed the point. Read it again. I wasn't implying water wouldn't come in the hole that is drilled. Water WILL get in no matter what you do. Might as well give it an easy way out, instead of sitting in the bottom of the box for weeks after a heavy rain. My preference is to install an open bottom quazite box with at least 6" of crushed stone under it anyway.

Never mind. When someone gets it in their head to argue I find it best to just to let them have their day. The op asked if he could drill a hole. I said yes. Feel free to tell him no if you like. Heck, at least TRY to answer his questions. At least one of them. As far as I can see, you have yet to contribute anything positive to this post. I wasn't aware the reason for this site is to sit back and ignore the op's questions and just criticize the answers others submit.

Your comment "who cares" tells me you have not read the op. He obviously does or he would not have asked the question.

Your comment "Underground work is all wet rated" tells me you didn't read my first post about using polaris blues, because they are rated for direct burial/ wet locations.

your comment "why make it easier for water to get in" tells me three things.
1. You didn't read the rest of my first post where I said "water will always find its way in".
2. you don't do much underground work or you would already know water will get in the box no matter what you do.
2. It also tells me you contradicted your own post that "if the work is done correctly the water will not make a difference" which I obviously agree with since I am not the moron you make me out to be. Or am I, and the whole blue polaris connectors thing was just a lucky mistake on my part. Like I said before. I don't get it. I answered the op and didn't clear it with you first. Is that it?